2017 Global Model Runs Discussion (Out to day 16)

[Alyono]

GFS doing the same thing with this system.

It develops systems that will not develop, but ignores the obvious developers. Seems it can only create low level vorticity via convection and not through dry dynamics

[WeatherEmperor]

Hey Alyono/other pro-mets. Is this another example of the convective feedback issues I hear about because of the very small depicted size of the storm??


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[cycloneye]

12z GFS once again has the MDR development.

[cycloneye]

120 hours.

[cycloneye]

126 hours.

[Alyono]

Hey Alyono/other pro-mets. Is this another example of the convective feedback issues I hear about because of the very small depicted size of the storm??


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check out how the system forms. Creates multiple areas of spurious vorticity from convection that congeal into a TC.

It's almost as if there are errors with the equations themselves with this "upgraded" GFS. A model today should not be having these kinds of issues

[cycloneye]

Moving still mainly west.

[cycloneye]

More WNW at 138 hours.

[cycloneye]

150 hours.

[Ivanhater]

Very weak ridging in the ATL

[RL3AO]

check out how the system forms. Creates multiple areas of spurious vorticity from convection that congeal into a TC.

It's almost as if there are errors with the equations themselves with this "upgraded" GFS. A model today should not be having these kinds of issues

Firing convection in the early morning along the ITCZ makes sense, but to have multiple areas of vorticity exceeding 50 x 10^-5 and 850 height falls of more than 30 meters in 12 hours in the deep tropics with a wave. That seems very off.

[Alyono]

check out how the system forms. Creates multiple areas of spurious vorticity from convection that congeal into a TC.

It's almost as if there are errors with the equations themselves with this "upgraded" GFS. A model today should not be having these kinds of issues

Firing convection in the early morning along the ITCZ makes sense, but to have multiple areas of vorticity exceeding 50 x 10^-5 and 850 height falls of more than 30 meters in 12 hours in the deep tropics with a wave. That seems very off.

Even the FIM8 is not showing development as of 0Z. There is probably some type of coding error with some of the equations with the GFS "upgrade". Only thing I can think of, as a full physics model cannot be this far off these days. This is like the 1980s

[cycloneye]

Only for the record of this thread,this is 12z CMC.

[AtlanticWind]

Maybe we should wait and see if the GFS solution is wrong before jumping to conclusions?

[RL3AO]

Even the FIM8 is not showing development as of 0Z. There is probably some type of coding error with some of the equations with the GFS "upgrade". Only thing I can think of, as a full physics model cannot be this far off these days. This is like the 1980s

This is what I got from a post-doc at GFDL.

New convective scheme entrains more dry air when RH is low, but allows for resolved and parameterized convection, especially in high RH. This is a high RH environment (like the EPAC), and so I think you're getting unrealistic convective feedback between grid and larger scales.

[Alyono]

Even the FIM8 is not showing development as of 0Z. There is probably some type of coding error with some of the equations with the GFS "upgrade". Only thing I can think of, as a full physics model cannot be this far off these days. This is like the 1980s

This is what I got from a post-doc at GFDL.

New convective scheme entrains more dry air when RH is low, but allows for resolved and parameterized convection, especially in high RH. This is a high RH environment (like the EPAC), and so I think you're getting unrealistic convective feedback between grid and larger scales.

the GFS is mixing parameterized and resolved convection? How does it get explicit convection with its grid spacing? You need less than 5 km for that!

I'll take the NAVGEM over this

[Alyono]

Maybe we should wait and see if the GFS solution is wrong before jumping to conclusions?

not when the model has a process that is physically incorrect

[cycloneye]

NHC doesn't buy GFS scenario.

[RL3AO]

NHC doesn't buy GFS scenario.

Fool me once, shame on you. Fool me twice...

[AtlanticWind]

Euro has a 1013 low sw of Cabo Verde islands,we will see if it does anything with it